You cannot be him but you can battle him in the Undead campaign.
You cannot be him but you can battle his army in a alliance mission
You cannot be him but you can battle him in the final orc mission
On Warcraft 3 you cannot be the centaurs in the mission but you only can play as the centaurs in the custom map.
There is no world of warcraft 3. There is world of warcraft, and warcraft 3. Unless you want to refer to Cataclysm. If so then no, you'd fail.
Of course it is. Battle.net still has full support for the game.
You can't play dota without installing warcraft 3.
Warcraft 2's expansion, Both Warcraft 3's and World of Warcraft are all online play. warcraft 2 and 3 use battle.net, while World of Warcraft is a paid subscription MMORPG
yes
Yes it is.
I have bought warcraft 3 RoC digitally and my computer has crashed, leaving me with no warcraft 3. I'd like to know if it's possible for me to redownload this and if anything won't work. No one else has my CD key so I should be fine right?
Sadly, you can't
It is not possible for a player to ban another player on warcraft 3. It is possible to kick a person in the middle of a public game, but this uses a third party program not supported, or condoned by Blizzard Entertainment.